NEW OPERATORS FOR ELECTRONIC DENSITY CALCULATION .2. APPLICATION TO HYDROGEN, FIRST-ROW ATOMS, AND FIRST-ROW DIATOMIC HYDRIDES

The first practical calculations using two new operators specifically designed for determination of electronic spin and charge density at nu clei are reported. Applications are given for hydrogen, first-row atom s, and first-row diatomic hydrides. Numerical grid methods that simula te complete basis set results confirm a number of relations previously derived formally for the new operators. They also serve as benchmarks for testing the practical utility of the new operators in calculation s with small to large Gaussian basis sets. In this connection, the new operators are generally found to have performance superior to the usu al delta function formulation and to an alternative one based on the H iller-Sucher-Feinberg identity. (C) 1996 American Institute of Physics .